LEDs on a Stick

Persistence of Vision – LEDs on a
Stick

Rob Demmer

Joey Barnes

Description:

This project uses LEDs blinking at very
high rates to create words when spinning. When not spinning, the
lights appear just to be turned on and not blinking but when spun,
the lights blink in such a way that the word “Hi” can be clearly
seen. The breadboard is mounted to a
rotating PVC pipe which allows for the device to spin. 5 LEDs are
attached to the breadboard along with the arduino system. The
aruduino board is powered by a 9V battery which is attached with
velcro to the bottom of the board and secured also with a rubber
band.

The code itself is very basic and
relies mostly on the order which the lights turn on and off and the
amount of delay in between. The variable “lightflash” is set to
equal to one so that the LEDs flash at the fastest rate possible.
“Lightflash” is only used within each individual “letter”
being created by the LEDs. A different delay amount is used between
the “H” section of the code and the “i” code. This is because
if the delay were to be set to “lightflash” the “letters”
being created would run into each other so to speak. With a greater
amount of delay time between the two sections of code, each “letter”
can be easily distinguished from one another and not blend together.

Problems Encountered :

The main problems encountered during
the making of the project were the initial code being written and
determining the speed the lights should flash at. This was difficult
because the code had to be adjusted to compensate for the short
radius of the spinning piece attached to the PVC pipe. Mounting the
board was also difficult because as we shortly found out during
testing, super glue was not able to securely hold the board together
with the PVC. After drilling a hole into the PVC and tying string
through it and to the board, along with more super glue, this problem
was solved.

If we could continue further:

With more time, money, effort, and
skill, we would have liked to mount the LEDs to a spinning motor so
it could rotate at a faster rate with a greater radius. This would
allow us to create more words through the coding and at the same time
make it able to see the words more clearly. Going even further, an
accelerometer could be attached to determine speed and then create
different words for different speeds.